Arthroscopic devices and methods

Abstract

A bipolar radiofrequency (RF) device for treating tissue in the presence of an electrically conductive fluid includes a headpiece and a probe. The handpiece has a motor drive, a receiving channel, and an active electrical contact on an inner wall of the receiving channel. A return electrical contact is disposed proximally of the active electrical contact on the inner wall of the receiving channel. A probe includes a proximal hub and an elongated shaft extending distally about a longitudinal axis from the proximal hub, and the hub being may be inserted into and removed from the receiving channel of the handpiece. A working end of the probe is located at a distal end of the elongated shaft, and the working end includes an active electrode and a return electrode. A return electrical contact is located proximally of an active electrical contact on an outer surface of the hub. In this way, the return electrical contacts in the receiving channel and on the outer surface of the hub, respectively, and the achieve electrical contacts in the receiving channel and on the outer surface of the hub, respectively, engage each other when the hub is inserted into the receiving channel of the handpiece.

What is claimed is: 
     
       1. A bipolar radiofrequency (RF) device for treating tissue in the presence of an electrically conductive fluid, comprising:
 a handpiece including a motor drive, a receiving channel, a first active electrical contact on an inner wall of the receiving channel, and a first return electrical contact on the inner wall of the receiving channel, wherein the first return electrical contact is disposed proximally of the first active electrical contact on the inner wall of the receiving channel; 
 a probe comprising a proximal hub and an elongated shaft extending distally about a longitudinal axis from the proximal hub, the proximal hub being configured for detachable insertion into the receiving channel of the handpiece; 
 a working end at a distal end of the elongated shaft, said working end including an active electrode and a return electrode; and 
 a second return electrical contact, the second return electrical contact located on an outer surface of the proximal hub and disposed proximally of a second active electrical contact on the outer surface of the proximal hub so that: (1) the first return electrical contact engages the second return electrical contact when the proximal hub is inserted into the receiving channel of the handpiece; and (2) the first active electrical contact also engages the second active electrical contact when the proximal hub is inserted into the receiving channel of the handpiece, 
 wherein the second active electrical contact is electrically coupled to an inner sleeve of the elongated shaft by a rotating collar that is fixedly attached to a proximal end of the inner sleeve. 
 
     
     
       2. The bipolar RF device of  claim 1 , wherein the probe comprises a flow channel extending through the elongated shaft to an exit port in the proximal hub that communicates with an interior chamber in the proximal hub, wherein the handpiece comprises an outflow passageway, and wherein an outlet end of the flow channel opens to the receiving channel through the inner wall of the receiving channel. 
     
     
       3. The bipolar RF device of  claim 2 , wherein the flow channel extends from a window in the working end to the exit port in the proximal hub and is configured for removal of fluids and tissue debris from a treatment site. 
     
     
       4. The bipolar RF device of  claim 3 , wherein the outflow passageway in the handpiece is configured for coupling to a negative pressure source. 
     
     
       5. The bipolar RF device of  claim 2  further comprising a first seal between the outer surface of the proximal hub and the inner wall of the receiving channel to inhibit fluid migration between: (i) where the first active electrical contact engages the second active electrical contact when the proximal hub is inserted into the receiving channel of the handpiece; and (ii) where the first return electrical contact engages the second return electrical contact when the proximal hub is inserted into the receiving channel of the handpiece. 
     
     
       6. The bipolar RF device of  claim 5 , wherein the first seal comprises a resilient member carried by at least one of the proximal hub and handpiece. 
     
     
       7. The bipolar RF device of  claim 5 , wherein a gap between the outer surface of the proximal hub and the inner wall of the receiving channel is sufficiently large to permit fluid migration from the interior chamber in the proximal hub through the gap when the proximal hub is inserted into the receiving channel of the handpiece. 
     
     
       8. The bipolar RF device of  claim 1 , wherein the second active electrical contact and the second return electrical contact each comprise a pair of diametrically opposed spring-loaded electrical contacts and the first active electrical contact and the first return electrical contact each comprise a ring electrode extending 360° about a full circumference of the inner wall of the receiving channel. 
     
     
       9. The bipolar RF device of  claim 8 , wherein the pair of diametrically opposed spring-loaded electrical contacts of the second return electrical contact are electrically coupled to an outer sleeve of the elongated shaft by a cylindrical core member which extends distally of where the first active electrical contact engages the second active electrical contact when the proximal hub is inserted into the receiving channel of the handpiece. 
     
     
       10. The bipolar RF device of  claim 1 , wherein the elongated shaft includes an outer sleeve, the inner sleeve concentrically received within the outer sleeve. 
     
     
       11. The bipolar RF device of  claim 10 , wherein the outer sleeve is electrically coupled to the second return electrical contact. 
     
     
       12. The bipolar RF device of  claim 11 , wherein the outer sleeve is electrically coupled to the second return electrical contact by a cylindrical core member in which the rotating collar is coaxially disposed. 
     
     
       13. A bipolar radiofrequency (RF) device for treating tissue in the presence of an electrically conductive fluid, comprising:
 a handpiece including a motor drive, a receiving channel, a first active electrical contact on an inner wall of the receiving channel, and a first return electrical contact on the inner wall of the receiving channel, wherein the first return electrical contact is disposed proximally of the first active electrical contact on the inner wall of the receiving channel; 
 a probe comprising a proximal hub and an elongated shaft extending distally about a longitudinal axis from the proximal hub, the proximal hub being configured for detachable insertion into the receiving channel of the handpiece; 
 a working end at a distal end of the elongated shaft, said working end including an active electrode and a return electrode; and 
 a second return electrical contact, the second return electrical contact located on an outer surface of the proximal hub and disposed proximally of a second active electrical contact on the outer surface of the proximal hub so that: (1) the first return electrical contact engages the second return electrical contact when the proximal hub is inserted into the receiving channel of the handpiece; and (2) the first active electrical contact also engages the second active electrical contact when the proximal hub is inserted into the receiving channel of the handpiece, 
 wherein the second active electrical contact and the second return electrical contact each comprise a pair of diametrically opposed spring-loaded electrical contacts and the first active electrical contact and the first return electrical contact each comprise a ring electrode extending 360° about a full circumference of the inner wall of the receiving channel, 
 wherein the pair of diametrically opposed spring-loaded electrical contacts of the second return electrical contact are electrically coupled to an outer sleeve of the elongated shaft by a cylindrical core member which extends distally of where the first active electrical contact engages the second active electrical contact when the proximal hub is inserted into the receiving channel of the handpiece, 
 wherein the pair of diametrically opposed spring-loaded electrical contacts of the second active electrical contact pass radially through the cylindrical core member and are electrically coupled to an inner sleeve of the elongated shaft by a rotating collar which is coaxially disposed in the cylindrical core member. 
 
     
     
       14. A bipolar radiofrequency (RF) device for treating tissue in a patient in the presence of an electrically conductive fluid, comprising:
 a handpiece including a receiving channel and an outflow passageway and being adapted for gripping by the hand of an operator; 
 a probe comprising a proximal hub and an elongated shaft extending distally about a longitudinal axis from the proximal hub to a working end of the probe that includes an active electrode and a return electrode, the proximal hub configured for detachable insertion into to the receiving channel of the handpiece, wherein a gap between an outer surface of the proximal hub and an inner wall of the receiving channel is sufficiently large to permit fluid migration through the gap when the proximal hub is inserted into the receiving channel of the handpiece; 
 a first active electrical contact on the inner wall of the receiving channel; 
 a second active electrical contact on the outer surface of the proximal hub, wherein the first active electrical contact and the second active electrical contact are adapted to engage one another to connect the active electrode to an RF source when the proximal hub is inserted into the receiving channel of the handpiece; 
 a first return electrical contact on the inner wall of the receiving channel; 
 a second return electrical contact on the outer surface of the proximal hub, wherein the first return electrical contact and the second return electrical contact are adapted to engage one another to connect the return electrode to the RF source when the proximal hub is inserted into the receiving channel of the handpiece; 
 a first seal in the gap between the outer surface of the proximal hub and the inner wall of the receiving channel; and 
 a flow channel extending through the elongated shaft and the proximal hub, the flow channel communicating with the outflow passageway in the handpiece when the proximal hub is inserted into the receiving channel of the handpiece, 
 wherein the first return electrical contact is disposed proximally of the first active electrical contact on the inner wall of the receiving channel, and wherein the second return electrical contact is disposed proximally of the second active electrical contact on the outer surface of the proximal hub, 
 wherein the second active electrical contact is electrically coupled to an inner sleeve of the elongated shaft by a rotating collar that is fixedly attached to a proximal end of the inner sleeve. 
 
     
     
       15. The bipolar RF device of  claim 14 , wherein a selected portion of a surface of the flow channel comprises a dielectric to thereby control a distance between the active electrode and the second return electrical contact. 
     
     
       16. The bipolar RF device of  claim 15 , wherein the distance is controlled to permit a limited RF current flow from conductive fluid in the interior chamber to said first return electrical contact and said second return electrical contact while maintaining sufficient RF current flow between the active electrode and the return electrode in the working end for igniting a plasma about the active electrode in use. 
     
     
       17. The bipolar RF device of  claim 14 , wherein the first seal is effective to inhibit fluid migration between: (i) where the first active electrical contact engages the second active electrical contact when the proximal hub is inserted into the receiving channel of the handpiece; and (ii) where the first return electrical contact engages the second return electrical contact when the proximal hub is inserted into the receiving channel of the handpiece. 
     
     
       18. The bipolar RF device of  claim 14 , wherein the first seal comprises a resilient member carried by at least one of the proximal hub and the handpiece. 
     
     
       19. A bipolar radiofrequency (RF) device for treating tissue in the presence of an electrically conductive fluid, the bipolar RF device comprising:
 a handpiece including a motor drive, a receiving channel, a first active electrical contact on an inner wall of the receiving channel, and a first return electrical contact on the inner wall of the receiving channel, wherein the first return electrical contact is disposed proximally of the first active electrical contact on the inner wall of the receiving channel; 
 a probe comprising a proximal hub and an elongated shaft extending distally about a longitudinal axis from the proximal hub, the proximal hub being configured for detachable insertion into the receiving channel of the handpiece; 
 a working end at a distal end of the elongated shaft, said working end including an active electrode and a return electrode; and 
 a second return electrical contact, the second return electrical contact located on an outer surface of the proximal hub and disposed proximally of a second active electrical contact on the outer surface of the proximal hub so that: (1) the first return electrical contact engages the second return electrical contact when the proximal hub is inserted into the receiving channel of the handpiece; and (2) the first active electrical contact also engages the second active electrical contact when the proximal hub is inserted into the receiving channel of the handpiece, 
 wherein the second active electrical contact is electrically coupled to an inner sleeve of the elongated shaft, 
 wherein the elongated shaft includes an outer sleeve, the inner sleeve concentrically received within the outer sleeve. 
 
     
     
       20. The bipolar RF device of  claim 19 , wherein the outer sleeve is electrically coupled to the second return electrical contact. 
     
     
       21. The bipolar RF device of  claim 20 , wherein a rotating collar is fixedly attached to a proximal end of the inner sleeve, and wherein the outer sleeve is electrically coupled to the second return electrical contact by a cylindrical core member in which the rotating collar is coaxially disposed.